检索结果-南通市图书馆

Analysis of 19-nortestosterone residue in animal tissues by ion-trap gas chromatography-tandem mass spectrometry

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 460-467页

作者： Jin-qing JIANG Lei zhang Guang-ling LI hai-tang zhang Xue-feng YANG Jun-wei LIU Ren-feng LI Zi-liang WANG Jian-hua WANG College of Veterinary Medicine Northwest A &F University Yangling 712100 China College of Animal Science Henan Institute of Science and Technology Xinxiang 453003 China College of Resources and Environment Henan Institute of Science and Technology Xinxiang 453003 China

A rapid sample treatment procedure for the gas chromatography-tandem mass spectrometry （GC-MS） determination of 19-nortestosterone （19-NT） in animal tissues has been developed. In our optimized procedures, enzymatic hydrolysis with β-glucuronidase from Escherichia coliwas performed in an acetate buffer （pH 5.2, 0.2 mol/L） Next, the homogenate was mixed with methanol and heated at 60℃ for 15 min, then placed in an ice-bath at -18℃ for 2 h. After liquid-liquid extraction with n-hexane, the analytes were subjected to a normal-phase solid phase ex- traction （SPE） C18 cartridge for clean-up. The dded organic extracts were derivatized with heptafluorobutydc anhydride （HFBA）, and then the products were injected into GC-MS. Using electron impact mass spectrometry （El-MS） with positive chemical ionization （PCI）, four diagnostic ions （mlz 666, 453, 318, and 306） were determined. A standard calibration curve over the concentration range of 1-20 ng/g was reached, with Y=467084X-68354 （R^2=0.9997） for 19-NT, and the detection limit was 0.3 ng. When applied to spiked samples collected from bovine and ovine, the recoveries ranged from 63% to 101% with relative standard deviation （RSD） between 2.7% and 8.9%. The procedure is a highly efficient, sensitive, and more economical method which offers considerable potential to resolve cases of suspected nandrolone doping in husbandry animals.

关键词： 19-Nortestosterone (19-NT) Gas chromatography-tandem mass spectrometry (GC-MS) Animal tissues

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of an indirect competitive ELISA for simultaneous detection of enrofloxacin and ciprofloxacin

引用

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第11期12卷 884-891页

作者： hai-tang zhang Jin-qing JIANG Zi-liang WANG Xin-yao CHANG Xing-you LIU San-hu WANG Kun ZHAO Jin-shan CHEN College of Animal Science Henan Institute of Science and Technology Xinxiang 453003 China Henan Higher Education Engineering Technology Research Center for Animal Diseases Control and Residues Supervision Xinxiang 453003 China

Modified 1-ethyl-3-(3-dimethylaminopropy) carbodiimide(EDC) method was employed to synthesize the artificial antigen of enrofloxacin(ENR),and New Zealand rabbits were used to produce anti-ENR polyclonal antibody(pAb).Based on the checkerboard titration,an indirect competitive enzyme-linked immunosorbent assay(ELISA) standard curve was *** assay was sensitive and had a linear range from 0.6 to 148.0 μg/kg(R2=0.9567),with the half maximal inhibitory concentration(IC50) and limit of detection(LOD) values of 9.4 μg/kg and 0.2 μg/kg,*** all the competitive analogues,the produced pAb exhibited a high cross-reactivity to ciprofloxacin(CIP)(87%),the main metabolite of ENR in *** optimization,the matrix effects can be ignored using a 10-fold dilution in beef and 20-fold dilution in *** overall recoveries and coefficients of variation(CVs) were in the ranges of 86%-109% and 6.8%-13.1%,*** can be concluded that the established ELISA method is suitable for simultaneous detection of ENR and CIP in animal tissues.

关键词： Enrofloxacin Ciprofloxacin Indirect competitive ELISA Animal tissues

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhancement of DNA vaccine-induced immune responses by a 72-bp element from SV40 enhancer

引用

Chinese Medical Journal 2007年第6期120卷 496-502页

作者： LI hai-shan LIU Yong LI Ding-feng zhang Ran-ran tang hai-li zhang Yu-wei HUANG Wei LIU Ying PENG Hong XU Jian-qing HONG Kun-xue SHAO Yi-ming State Key Laboratory for Infectious Disease Prevention and Control National Center for AIDS/STD Control and Prevention Chinese Center for Disease 100050 China

Background Although DNA vaccine is considered as the next generation of vaccine, most DNA vaccine candidates are still suffering from the relatively weak immunogenicity despite the increased dosage of plasmid DNA administered. In order to enhance the immune responses elicited by a codon-optimized HIV gag DNA vaccine, a modified plasmid vector pDRVI1.0 and a booster immunization with replicating Tiantan vaccinia （RTV） strain expressing the same gene were employed. Methods Vector pDRVI1.0 was constructed through inserting the 72-bp element from the SV40 enhancer, which was reported promoting nuclear transport of plasmid DNA, to the upstream of cytomegalovirus enhancer/promoter region of the plasmid vector pVR1012. Gene expression levels from expression plasmids based on pDRVI1.0 and pVR1012 were tested. Humoral and cellular immune responses induced by DNA vaccine alone or DNA prime-RTV boost regimen were determined in mice. Results It was shown that the 72-bp element significantly enhanced the gene expression level in non-dividing cells. gag-specific humoral and cellular immune responses induced by DNA vaccination were both significantly improved, while the Thl/Th2 balance was not obviously affected by the 72-bp element. RTV boosting further significantly enhanced DNA vaccine-palmed antibody and T cell responses in a Thl-biased manner. Conclusions The 72-bp SV40 enhancer element should be included in the DNA vaccine vector and RTV strain is a very efficient live vector for boosting immunization.

关键词： DNA vaccines SV40 enhancer prime-boost vaccinia Tiantan strain

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

引用

Science China Chemistry 2025年第1期68卷 186-191页

作者： hai Zou Yunfeng Bao Xueshang Xin Yu Qi Tengfeng Xie Fuxiang zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Prediction and optimization of flue pressure in sintering process based on SHAP

引用

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 346-359页

作者： Mingyu Wang Jue tang Mansheng Chu Quan Shi Zhen zhang School of Metallurgy Northeastern UniversityShenyang 110819China Liaoning Low-Carbon Steelmaking Technology Engineering Research Center Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-Carbon Steelmaking(Ministry of Education) Shenyang 110819China

Sinter is the core raw material for blast *** pressure,which is an important state parameter,affects sinter *** this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment ***,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction *** effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment *** operating parameter combination was then *** flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect.

关键词： sintering process flue pressure shapley additive explanation prediction optimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

引用

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo Li Fu tang Jingkai zhang Yuetong Kang Hean zhang Lidong Li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Propagating subduction initiation of the Caroline Plate at the Mussau Trench

引用

Science China Earth Sciences 2025年第1期68卷 253-269页

作者： Chun-Feng LI Yongkang DENG Tao WU Dongdong DONG Guoliang zhang Jiazheng zhang Yutao LIU Yaqing LI Fugui tang Lulu zhang Department of Marine Sciences Zhejiang University Laboratory of Marine Mineral Resources Laoshan Laboratory Key Lab of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Lab of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Science & Technology on Integrated Information System Lab Institute of Software Chinese Academy of Sciences

New seismic imaging from the Mussau Trench confirms that, under horizontal compression on an oceanic plate boundary, it is within the young and weak oceanic plate that a trench will develop, and it is the young plate, not so long after its birth, that starts to subduct toward the old plate. The Mesozoic Pacific Plate cannot easily bend, under the joint horizontal compression and vertical gravity pull, even with a pre-existing weak zone in place and with a large age offset across the plate boundary. The bending of the Caroline Plate near the northern end of the Mussau Trench started only after a long-time span of trench migration, and/or after a prolonged transition from initial compression to trench development. Highly contrasting trench deformation and sedimentary accretion between two parallel seismic sections support an evident migration of underthrusting or significant longitudinal heterogeneity along the trench. The swift transition from underthrusting to non-thrusting can be explained by a counter-clockwise rotation of the Caroline Plate. That miniature accretionary wedges develop even before the subduction initiates imply strong compression and uplifting before the underthrusting can kick-start. Rotation of the Caroline Plate have been halted as the Mussau Trench is seismically rather quiet and the Lyra Trough to the east shows relaxational extension.

关键词： Mussau Trench Subduction initiation Seismic reflection Caroline Plate

来源：

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

引用

Tungsten 2025年第1期7卷 1-31页

作者： Qiao Xie Ying-Jie Yu hai-Jun zhang Ya-Ping Deng Wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

关键词： Electrocatalytic Energy conversion High-entropy alloys Structural modulation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

电弧加热发动机喷出等离子体静电单探针测量

引用

推进技术 2011年第6期32卷 889-894页

作者：何艳汤海滨张尊北京航空航天大学宇航学院北京100191

应用静电单探针测量了kW级电弧加热发动机喷出等离子体参数分布。发动机以氮气为推进剂,测量范围为距离发动机喷口1.25～15cm,实验中真空舱压力为3～5Pa。实验获得了电子温度和电子数密度沿不同轴向位置和径向位置的变化规律,电子温度为... 详细信息

应用静电单探针测量了kW级电弧加热发动机喷出等离子体参数分布。发动机以氮气为推进剂,测量范围为距离发动机喷口1.25～15cm,实验中真空舱压力为3～5Pa。实验获得了电子温度和电子数密度沿不同轴向位置和径向位置的变化规律,电子温度为0.4～0.8eV,电子数密度为1.2×1017～1.25×1018m-3。对比研究发现,N2为推进剂产生的等离子体的电子温度和电子数密度均大于N2-H2为推进剂的情况,但前者发散角较小。

关键词：电弧加热发动机静电单探针等离子体诊断

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries

引用

Nano-Micro Letters 2025年第1期17卷 176-190页

作者： Xiaohong Zou Qian Lu Mingcong tang Jie Wu Kouer zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao zhang Zongping Shao Liang An Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and TechnologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Department of Chemistry The Chinese University of Hong KongMa Lin BuildingShatinHong Kong SAR 999077People’s Republic of China WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China

Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe *** is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe *** the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.

关键词： Catalyst-support interaction Supported catalysts Heterointerface Oxygen evolution reaction Zn-air batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：